Stackable washer and means for fabricating the same



F. D. WENN' Aug. 25, 1936.

STACKABLE WASHER AND MEANS FOR F ABRICATING THE SAME Filed Dec. 16, 1935Fwvo D WEWA/ INVENTOR.

A TTORNEY Patented Aug. 25, 1936 UNITE s'rn'res PATENT OFFIE STACKABLEwAsnna ANDMEANS FOR FABRICATING THE SAME Floyd D. Wenn, Binghamton, N.Y., assignor to The Brewer-Titchener Corporation, Cortland, N. Y., acorporation of New York 1 This invention relates to a certain article ofmanufacture and novel die appliances for its economical fabrication on arapid production scale without material product wastage, and whicharticle may comprise a dished sheet metal washer or the like centrallyperforated disc adapted to receive a cooperating rivet. Myimprovementsthereon are more particularly directed to, the eliminationof the burr or ragged edge that is generally formed at the marginalregion of a washer aperture while strip stock is being pierced byconventional gang punching appliances, particularly so after the dieshave become some? what dull.

In modern practice, such eyelet devices are being extensively utilizedand magazine fed in rapid succession by initially stringing a stack ofWashers in nested relation upon a rod or the like carrier means. Theundermost of such stored Washers is then individually wiped sidewise ofsaid stack by suitable transfer means with the intent to singly withdrawthe same in sequence from said stack for placement upon distributedrivets or the like Work pieces. In such associa-. tion, it has beenfound that the cited burr rough.- ness when uncorrected, is likely toseriously in:- terfere with the desired regularperformance of a magazinefeed in that the washers frequently fail to transfer properly andthereby cause oer.- tain of the rivets to be devoid of washers or allowmore than one such washer to be fed there.-. to at a time It will beevident that any such disturbances slow up production and in otherrespects augment fabrication cost when applied for instance, to themaking and attaching of. rubber shoe heels or analogous products.

To the end that the cited deficiency maybe overcome, I purposelyintroduce a special stepin the making of my washer which consists incoining, cold swaging or otherwise reshaping the cited metallic burraround the perimeter of the pierced aperture so as to form a smoothlyround.- ed or chamfered edge that will substantially eliminate irregulardrag behavior without having to individually transfer or otherwisehandle such washer product prior to the final blanking thereof. Thisaspect assumes importance because of the rapid rate at which it isherein contemplated to simultaneously fabricate substantially perfectwashers asregards present'needs by the use of multiple gang agenciesthat operate in unison upon common strip stock and which agencies areadapted to continuously duplicate such product over a long operatingperiod regardless of normaldie wear .or other minor punchdefects.

My improvements insure that any one such washer will more freely slipsidewise from beneath a stack in order that they may be automaticallyfed without fail from a magazine carrier without dra ging an additionalwasher along therewith.

The object of my invention is to provide means for fabricating a washerof the character indicated that shall be laterally stiff at the minofmetal requirement and one whose dished cross-sectional profile ispreferably so shaped that when centrally pierced with a smallcylindrical hole, the last sheared or exterior perimetric edge thereofwill by special processing be smoothly chamfered to eliminate the citedabnormal burr drag, all such fabrication steps being completed prior toblanking the respective washer perimeters out of strip stock.

Reference is bad to the accompanying one drawing sheet which isillustrative of a preferred embodiment of my washer device includingappurtenances for fabricating the same on an in-. tensive basis, and inwhich: i

Fig. 1 represents a face view of my improved washer in magnified scale,and Fig. 2 shows a sectional profile thereof taken along line A,A.

Fig. 3 schematically depicts a gang die that may be employed in themaking of my washer.

' Attention will first be directed to the article which'may comprise asubstantially flat annular brim flange portion Hl made of sheet metaland having a dished medial washer region that is here indented to formconical stiffening faces ll of which the central apex region is showncylindrically apertured at E2 by the use of a suitable piercing punch.It is preferred to so shape the washer profile as to leave a narrowinner ledge portion H3 contiguous to said aperture. One marginal face ofthe brim flange may be kept somewhat Wider than its opposed face andwhich widths are respectively designated WI and W2. The disposition issuch that when the conical faces are stacked as indicated by dottedoutline in Fig. 2, a small clearance gap [3 may be provided between thebrim flanges of consecutive washers.

As will presently appear, the aperture l2 and the brim flange lil arepunched out of strip stock in a down stroke. The last sheared uppermostedge of the flange iii is then likely to tear away to some extent andleave a slightly raised perimetric burr M. Said clearance gap i3 affordsroom for unobstructedly receiving such burr when the conical faces aresnugly nested upon a carrier rod or otherwise stacked in a conventionalmanner. Such adjacent washers may be individually slid axially crosswiseof each other without abnormal drag on part of the perimetric burr.

Because the inclined washer faces are snugly nested, the inner draggedburr as represented in ragged outline, is initially formed adjacent tothe lower sheared or exterior perimetric edge of the aperture [2 and assuch is likely to prove far more troublesome when applied to presentpurposes. To eliminate the lateral drag effect thereof, I subject theburr l5 in a cold state to a novel coining or the like swaging operationto give said edge a smoothly rounded chamfer having a relatively smallradius R. When fabricated thus, my improved washer is freed from allobnoxious burr drag and thus allows of regularly using transfer feedmagazines for prolonged periods without encountering operatingdisturbances such as missing a washer or dragging another alongtherewith. Heretofore, considerable quantities of completed washers havehad to be rejected because of the progressively increasing burrformation resulting from die wear.

It is emphasized that as applied to shoe making machinery and the likeautomatic devices, the washers needed are usually of a small sizeranging between to inch diameter of which enormous quantities are nowbeing marketed. The pierced aperture I2 requires a slender punch whosefrail cutting edge is likely to chip, wear or otherwise become defectivewhen operated at a high productive rate. In order to minimize thefabrication cost of such a small article without requiring individualhandling, it is preferred to strike my washers out of relatively thinstrip stock by the use of gang punch press methods and to correct forany dragged burr defects before finally severing the washer from thestrip stock. Such procedure permits the use of inherently simple, highspeed gang dies in which the unsevered washer is intermittently advancedfrom station to station and all pierced or blanked fragments are allowedto freely fall away from the dies by gravity.

As an exemplification, attention is directed to Fig. 3 that'illustratessuch processing and which successive steps may readily be carried outsimultaneously in multiple punch units of this kind to facilitate rapidwasher production. The metallic strip stock 26 is then progressivelyadvanced lengthwise by suitable means between the upper and lower dieblocks 2| and 22. The first step thereon may be performed by theindenting punch member 23 having a depending impression tip 24 whichcooperates with a tubular lower die 25 to form a conical or the likecross-sectional depression 26 in such stock. This indenting station isnot essential and may be omitted.

The next adjacent block members may comprise the piercing punch 27 andits cooperating seated die 28 serving to puncture a small aperture 29through the apex of the strip depression, the perimeter of said aperturebeing located wholly within the marginal confines of the dishedformation 25. The cited inner burr I5 is likely to be formed on thelower aperture edge by the punch drag, its extent depending upon theprevailing sharpness or other operative condition of the cutters. Thenext onward gang station is centered in a swaging die of which the upperdie member 39 is provided with a socketed projection that seats into thestrip indentation 26 while its cooperating lower punch member 3| isequipped with an upstanding tit extension 32 which is sized to snuglyenter the potential washer aperture 29 so as to maintain the cylindricalsize thereof. This operation serves to crush or upset said burr I5 andbring about a filleting of the lower aperture edge sufficiently smoothto accomplish the desired free slippage of washers, when stacked.

The strip is thereupon advanced to the next die station which comprisesa blanking punch 33 and a companion lower die 33 arranged to shear theouter perimeter of my washer as indicated by dotted outline in Fig. 3.The finished washer is allowed to drop through the last named die whenit is ready for use, the burred aperture edge having been smoothlycoined in the process of making and having required no individualhandling to perfect the same. It will be obvious that the outer burrededge may at increased fabrication cost, be struck up or otherwiseprocessed subsequent to the cited blanking operation, although this stepis ordinarily not required to meet present needs.

While only a single set of complete die components are illustrated, itwill be understood that multiple sets of such dies are usually mountedbetween a common pair of blocks so as to act simultaneously upon thestrip stock 2%). The present instrumentalities provide for a series ofdifferent kinds of punches such as 2? and 33 which respectively headdown upon their cooperating dies 28 and 34 and these have a reverselymounted punch 3| and an overhead die 30 interposed therebetween. The tit32 is shaped to pre- Vent contraction in the diametral size of thepierced aperture 29 while the dragged inner burr I5 is being coinedaround the entire perimeter of such aperture. During this operation, thesheared upper edge of such cylindrical aperture is not deformed whiledistorting the lower edge thereof and the hole size is maintained toproperly fit around a specified carrier rod. In addition, the overallheight or finished washer thickness is held to a substantially fixeddimension, irrespective of the initial projection on part of the draggedinner burr l5 that may ensue because of a change in the condition of anyone of such multiple piercing punches.

When fabricated in accordance with my teachings, such washers areenabled to slip laterally without undue burr drag and when stacked in amagazine, can be selectively shifted by automatic transfer means withthe assurance that not more than one such will be picked up at a time.This aspect assumes commercial importance for the reason that theproduct to which my washer may be applied, is thereby renered moreuniform and free from vexing operating delays While fabricating suchcompleted product on a large scale output basis.

As an article of manufacture, a distinctive structural feature of mywasher may be recognized by the comparatively smooth feel that has beenimparted to its pierced aperture edge, a characteristic that may morereadily be detected by microscopic examination.

When processed as described, the tool upkeep costs may be materiallyreduced since the same keen cutting edge need not be maintained ascompared with a process in which the burr drag has not been corrected;that is to say, without the use of my interposed coining dies 39 and 3|,only the first run batch of conventional washers are likely to havetheir respective apertures so neatly sheared by newly ground dies as toform no significant aperture'burr 5. The piercing punch 2'! generallybeing of a small diametral size,the wear of its cutting edge isinherently rapid and-likely to allow a large quantity of washers to befabricated before a prevailing dull condition is perceived by the pressattendant. Byvirtue of my improvements, I am enabled to more than doubledie production between grindings and provide for effectively usablewashers that do not require continuous close inspection. As a result,the wastage by returned unfit washers is reduced to a minimum.

Occasional product inspection is sufficient to check up the performanceof my machine, which practice has proven capable of delivering anassured high grade output without need of frequent shut down in which totrim the cutting tools or to replace punches. All such interferencesseriously conflict with successful commercial production of a-relativelylarge quota of usable washers and otherwise vitally restrict the profitmargin thereon. By introducing "the cited coining step, the piercingimplements need not be kept up to the same exacting standard and anoteworthy betterment in productive results is to be had.

As will be understood by those skilled in this art, the disclosed washerimprovements find a wide variety of uses and various structuralchangesin the details or processing thereof may be resorted to inlikewise carrying out my illustrative embodiments, all without departingfrom the spirit and scope of my invention heretofore described and moreparticularly defined in the appended claims.

I claim:

1. An article of manufacture comprising a plurality of stackable washersfabricated by blanking the same out of strip stock and of which eachwasher is provided with a relatively flat brim flange component disposedto circumscribe a centrally dished component that is cross-sectionallyshaped into a substantially conical profile having a cylindrical holepierced axially through the apex region thereof and the exteriorperimetric edge of which hole prior to blanking the washer is smoothlychamfered inwardly in a direction away from the apex of such profile,said chamfered edge of each such washer serving to facilitatesuperficial slippage between adjoining faces when the washers arestacked in nested relation and allowing one of the outermost washers tobe singly wiped sidewise of its hole axis relative to the next adjacentwasher without abnormal frictional drag.

2. An article of manufacture comprising a plurality of stackable washersfabricated by blanking the same out of strip stock and. of which eachwasher is provided with a relatively flat brim flange component whoseopposite side faces are given different Widths and which flangecircumscribes a centrally dished component that is cross-sectionallyshaped into a substantially conical profile having a cylindrical holepierced axially through the apex region thereof and the exteriorperimetric edge of which hole prior to blanking the washer is smoothlychamfered inwardly in a direction away from the apex of such profile,said washers when stacked in nested relation leaving a gap between eachsuccessive pair of brim flanges and which charnfered edge facilitatessuperficial slippage between adjoining washer faces to allow one of theoutermost washers to be singly wiped sidewise of its hole axis relativeto its next adjacent washer without abnormal frictional drag.

'3. A gang press agency for fabricating washers and whichagencycomprises a series of stations operated in unison and arranged tosuccessively treat a common strip of flat stock when said stock isintermittently advanced bodily from station to station, such consecutivestations respectively being equipped with different punch and die meansfor performing the following operations upon said stock in sequence,viz: firstly, piercing a cylindrical hole through said stock and whichhole has a burr dragged outwardly away from one edge thereof; then'swaging to coin the entire perimeter of said one edge and therebysubstantially free the burr therefrom; and lastly, blanking a washer outof said stock by shearing the washer perimeter subsequent to coining thehole thereof.

' 4. A gang press agency for fabricating washer having a brim flange andwhich agency comprises a series of stations operated in unison andarranged te successively treat a common strip of flat stock when saidstock is intermittently advanced bodily from station to station, suchconsecutive-stations respectively providing different punch and diemeans for performing the following operations upon said stock insequence, vizi firstly, conically indenting one side face of said stock;then piercing a cylindrical hole in the apex region of said indentationto provide for a potential washer having a burr dragged outwardly awayfrom one edge of said hole; thereupon swaging to coin said one edge andthereby substantially free the burr therefrom; and lastly, blanking thecoined potential washer out of said stock by shearing exteriorly aroundsaid identation to include a circumscribing brim flange within thewasher perimeter.

5. A gang press agency for fabricating washers and which agencycomprises three stations mounted in series between a fixed block and asuperimposed relatively movable block arranged to successively treat acommon strip of flat stock when said stock is intermittently advancedbodily from station to station, each such station being equipped with apunch member and a cooperating die member of which the punch members ofthe first and last stations are carried by the movable block and theinterposed station has its punch member reversely carried by the fixedblock for performing the following operations on said stock in sequence,viz: firstly, piercing a cylindrical hole through said stock and whichhole has a burr dragged outwardly away fro-m one edge by the piercingthereof; then, swaging to coin said one edge to substantially free theburr therefrom; and lastly, blanking a washer out of said stock byshearing the washer perimeter subsequent to coining the hole thereof.

6. A gang press agency for fabricating washers and which agencycomprises three stations mounted in series between a fixed block and asuperimposed relatively movable block arranged to successively treat acommon strip of flat stock when said stock is intermittently advancedbodily from station to station, each such station being equipped with apunch member and a cooperating die member of which the punch members ofthe first and last stations are carried by the movable block and theinterposed station has its punch reversely carried by the fixed block,the first of said punches serving to pierce a cylindrical hole throughthe stock on a down stroke of the movable block to leave a dragged burrextending outwardly away from the lower edge of said hole, and whichinterposed station on the next down stroke serves to substantially freesaid lower edge of the burr formed while piercing a hole through saidstock, and which last station serves to blank a washer out of said stockon the next following stroke, the first and last dies being disposed toallow the respective severed strip fragments to fall away from theirrespective dies by gravity.

7. A gang press agency for fabricating washers and which agencycomprises a series of stations operated in unison and arranged tosuccessively treat a common strip of flat stock when said stock isintermittently advanced bodily from station to station, such consecutivestations respectively providing diiferent punch and die means forperforming the following operations upon said stock in sequence, viz:firstly, piercing a cylindrical hole through said stock and leaving adragged burr extending outwardly away from one edge of said hole, thendeforming the entire perimeter of said one edge to free the burrtherefrom without deforming the other edge of said hole and therebymaintaining a definite overall thickness for the potential washerirrespective of the extent to which said burr may initially have beenleft on said one edge; and lastly, blanking the washer out of saidstock.

8. A gang press agency for fabricating washers at a high productive rateand which agency comprises three stations mounted in series between afixed block and a superimposed relatively movable block arranged tosuccessively treat a common strip of fiat stock when said stock isintermittently advanced bodily from station to station, each suchstation being equipped with a punch member and a cooperating die memberof which the punch members of the first and last stations are carried bythe movable block and the interposed station has its punch reverselycarried by the fixed block, the first of said punches serving to piercea cylindrical hole through the stock on a down stroke of the movableblock and leaving a dragged burr extending outwardly away from the loweredge of said hole, said interposed station on the next down strokeserving by a coining operation to substantially free said lower edge ofits burr, the reversed punch of said interposed station being providedwith tit means enterable into said hole to maintain the pierceddiametral size thereof while the strip is being coined, and which laststation serves to blank a washer out of said stock on the next followingstroke.

FLOYD D. WENN.

